Erin fought a dragon with $9$ heads. Then she fought another dragon with $2$ fewer heads than the first dragon. How many heads did the second dragon have?
Answer: To find how many heads the ${\text{Second dragon}}$ has, we start with the number of heads the ${\text{First dragon}}$ has and subtract ${2}$. $9$ $?$ $2$ First Dragon Second Dragon 2 ${9} - {2} = {\Box}$ Let's subtract to find how many heads the ${\text{Second Dragon}}$ has. $$ $$ ${-}$ $$ ${=}$ $$ $$ ${9} - {2} = {7}$ The second dragon had ${7}$ heads.